She will take up the role of senior consultant, with responsibility for the direct marketing and digital sectors.
Constable will work with Andrew Melsom, the intermediary's managing director, and will be briefed with developing client and agency relations within these two key areas.
She began her career at Wunderman as an account executive, before spending three years at Rapp Collins. She then worked in the marketing department at BSkyB. Following that, Constable spent eight years at Craik Jones Watson Mitchell Voelkel, before her 1999 move to the AAR.
Constable said: "I am looking forward to having a much broader client-facing role, and helping Agency Insight with all of its agency consultation needs, from pitches to relationships with agencies."
Melsom added: "She's going to bring increased knowledge of direct marketing and digital. She'll be doing DM and digital in addition to other consultancy work for Diageo, HSBC and Vodafone."